Message ID | CAHACq4o0k1RsGpn9XhjiPQ7qj+3JkPJLwW4xD4WPEkk6C0N+RQ@mail.gmail.com |
---|---|
State | New |
Headers | show |
I've committed this patch. -cary 2013-06-10 Cary Coutant <ccoutant@google.com> gcc/ * dwarf2out.c (hash_external_ref): Use die_symbol or signature for hash so that hash table traversal order is deterministic. > Index: gcc/dwarf2out.c > =================================================================== > --- gcc/dwarf2out.c (revision 198260) > +++ gcc/dwarf2out.c (working copy) > @@ -7385,7 +7385,22 @@ static hashval_t > hash_external_ref (const void *p) > { > const struct external_ref *r = (const struct external_ref *)p; > - return htab_hash_pointer (r->type); > + dw_die_ref die = r->type; > + hashval_t h = 0; > + > + /* We can't use the address of the DIE for hashing, because > + that will make the order of the stub DIEs non-deterministic. */ > + if (! die->comdat_type_p) > + /* We have a symbol; use it to compute a hash. */ > + h = htab_hash_string (die->die_id.die_symbol); > + else > + { > + /* We have a type signature; use a subset of the bits as the hash. > + The 8-byte signature is at least as large as hashval_t. */ > + comdat_type_node_ref type_node = die->die_id.die_type_node; > + memcpy (&h, type_node->signature, sizeof (h)); > + } > + return h; > } > > /* Compare external_refs. */
Index: gcc/dwarf2out.c =================================================================== --- gcc/dwarf2out.c (revision 198260) +++ gcc/dwarf2out.c (working copy) @@ -7385,7 +7385,22 @@ static hashval_t hash_external_ref (const void *p) { const struct external_ref *r = (const struct external_ref *)p; - return htab_hash_pointer (r->type); + dw_die_ref die = r->type; + hashval_t h = 0; + + /* We can't use the address of the DIE for hashing, because + that will make the order of the stub DIEs non-deterministic. */ + if (! die->comdat_type_p) + /* We have a symbol; use it to compute a hash. */ + h = htab_hash_string (die->die_id.die_symbol); + else + { + /* We have a type signature; use a subset of the bits as the hash. + The 8-byte signature is at least as large as hashval_t. */ + comdat_type_node_ref type_node = die->die_id.die_type_node; + memcpy (&h, type_node->signature, sizeof (h)); + } + return h; } /* Compare external_refs. */